Chapter 2.4, Problem 18P

You may combine your answers to all three parts of this problem.

a. Is it valid to compare

   $\frac{30}{70}$ and $\frac{20}{50}$

by “cancelling” the 0s and comparing

   $\frac{3}{7}$ and $\frac{2}{5}$

instead? Explain your answer.

b. Is it valid to compare

   $\frac{15}{25}$ and $\frac{105}{205}$

by “cancelling” the 5s and comparing

   $\frac{1}{2}$ and $\frac{10}{20}$

instead? Explain your answer.

c. Write a paragraph discussing the distinction between your answer in (a) and your answer in (b).